竹材弦面纵向切削的研究

研究了竹材弦面纵向切削的3种切削方式(单劈刀切削、单刨刀切削及并列式双刨刀切削)及单刨刀切削时的切削阻力,结果表明:对竹材采用劈或刨的切削方式,均可进行弦面纵向切削并能获得质量较好的竹蔑。竹材的节间、节部、切削厚度、含水率及切削速度等因素对切削阻力均有不同程度的影响。节部切削阻力明显高于节间切削阻力;切削阻力随切削厚度的增大而增大,两者成线性关系;含水率增大时,节间切削阻力减小,而节部切削阻力变化不大;切削速度增大时,节间切削阻力基本上是下降的,而节部切削阻力是增大的。     

庆元毛竹林园区开发技术

简述了庆元山区毛竹林开发的历程,分析了毛竹林开发的潜力、优势和发展前景,总结了近几年来毛竹林园区开发经验,形成了以园区开发为模式的毛竹林开发技术成果.     

龙竹竹材吸湿膨胀特性研究

对龙竹竹材的吸湿膨胀特性进行了测试和分析。结果表明,竹材各个方向上吸湿膨胀特性差异显著,且竹间部位和竹节部位的吸湿膨胀特性也有一定差异。     

毛竹残次林改造试验报告

１９８７～１９９０年，对３５１５ｈｍ２残次毛竹林试验区进行４年２度的砍杂、全垦、全垦结合施肥３种不同的作业方式的对比试验，试验结果均比试验前取得了显著的效益，其平均立竹量由１７１６支／ｈｍ２增加到３０７５支／ｈｍ２，平均胸径由６．６７ｃｍ增加到８．９１ｃｍ，平均度产新竹由３７８０ｋｇ／ｈｍ２增加到１５０９０ｋｇ／ｈｍ２，平均度产竹笋由５７０ｋｇ／ｈｍ２增加到２４３０ｋｇ／ｋｍ２，度产值由７９５元／ｈｍ２增加到３２３５．５元／ｈｍ２，投入产出比为１：７．０８。３种作业方式的比较，以全垦结合施肥为最好。     

多效唑调控观赏竹生长的初步研究

竹笋施用多效唑后,对其新梢日平均生长量及成竹后全竹高,枝下高、节间长、叶面积均有显著的抑制作用,注射处理在浓度300～800 mg·kg-1,喷施处理在浓度300～1000 mg·kg-1范围内,随处理浓度递增,抑制作用更为显著.应用多效唑能提高观赏竹的观赏价值,解决盆景制作的矮化及枝叶美化问题.     

毛竹笋用林梅前开山施肥试验初报

通过2年的梅前开山，施肥和大量挖掘鞭笋，增挖冬笋的试验，笋产量及产值分别比原来增长49．62％，57．95％，纯收入增加75．82％，每工值增加43．53％，投入产出比1：3．37。     

丛生竹防霉处理研究

通过选用多种防霉剂,采用不同的处理方法来对丛生竹进行防霉处理,分别进行室内存放1 a后检验和恒温恒湿箱快速检验来判定防霉效果,对几种处理方法的优缺点进行比较,从中筛选出针对不同使用场合处理的优良防霉剂。     

Observations of Phytophthora spp. in Water Recirculation Systems in Commercial Hardy Ornamental Nursery Stock

Samples of water and sediment were taken from drains, reservoirs and wells from four commercial hardy ornamental nurseries with water recirculation systems. The samples were taken on seven different dates throughout a single year from August 1994 to July 1995. The samples were screened for Phytophthora species using five different methods: direct plating, three bait tests (using lupin seedlings, apples and Rhododendron leaves) and a DAS-ELISA (double-antibody sandwich enzyme-linked immunosorbent-assay) with two antisera. In the nurseries with old water recirculation systems, Phytophthora species were detected in the drains and in the reservoirs. In the nursery with a new recirculation system, the pathogens were only present in the drains. None of the water samples from wells in any of the nurseries were contaminated. Phytophthora species were present in the water as well as in the sediment samples from drains and reservoirs. They were detected in the water recirculation systems irrespective of the season. The number of isolates increased about sevenfold between late summer and spring. At least 12 different Phytophthora species were identified: some isolates were previously unrecorded species. The epidemiology of the pathogens in outdoor water recirculation systems as well as the importance of the results for commercial nurseries is discussed.     

Indole-3-acetic acid biosynthesis in <Emphasis Type="Italic">Aciculosporium take</Emphasis>, a causal agent of witches' broom of bamboo

 Aciculosporium take (Ascomycota; Clavicipitaceae) is a causal agent of witches' broom of bamboo plants. The symptoms of this disease are believed to be induced by plant hormones, particularly auxins. Indole-3-acetic acid (IAA) was identified in cultures of this fungus in an l-tryptophan-supplemented liquid medium. IAA production was confirmed on 30 isolates of A. take from various hosts and locations at levels up to 1 mg/l. The biosynthetic pathway of IAA in A. take culture was examined by analyzing intermediate products and by feeding experiments. The results showed that the indole-3-pyruvic acid pathway (l-tryptophan → indole-3-pyruvic acid → indole acetaldehyde → IAA) was the dominant pathway in A. take. Received: June 3, 2002 / Accepted: July 25, 2002